Pump lubricating means



Feb. 8, 1.949. (g, F, DUERR, JR 2,460,814

PUMP LUBRI CAT ING y MEANS Feb. 8, 1949. C, F DUERR, JR 2,460,814

` PUMP LUBRICATING MEANS Filed May 9, 1945 2 Sheets-Sheet 2 i IN VEN TOR. Car/ l/err, -n/r BY//wff 61W/ Patented Feb. 8, 1949 UNITED STATES PATENT OFFICE PUlWP LUBRICATING MEANS Cleveland, Ohio Application May 9, 1945, Serial No. 592,787

3 Claims. l

This invention relates to means for lubricating pumps of the type that pump air and other gases; and particularly to lubricating means actuated by pump produced vacuum.

The lubricating means described herein is applicable to pumps of various types and as used for various purposes; and illustrative thereof is the pumping unit disclosed in the co-pending application of Ervin J. Osterhus, Serial Number 591,323, I'lled May 1, 1945, to which is applied a lubricator similar to that of the present invention.

According to the present invention, the vacuum developed at the intake side of an air or like pump is utilized to actuate a lubricator and draw lubricant such as oil into the pump.

This principle in general has been utilized heretofore; but in all such prior arrangements of which I have knowledge the amount of oil or rate of feeding of it to the pump varies with the amount of vacuum drawing it in; and if the rate of lubricant feed is set so as to be suflicient at low pump vacuum, it is excessive at high vacuum, and if it is set to be correct for high vacuum it is insufIicient at low vacuum.

According to another prior practice, pump lubricating oil is supplied from a reservoir by a metering arrangement continuously supplying oil, drop by drop for example, at a measured rate; but, in such arrangements, the feeding of oil goes on even after the pump is stopped, and therefore will flood the pump and uselessly deplete the oil supply, unless care and attention is exercised to cut the feed on and off as the pump is used intermittently.

It is desirable for various reasons to feed lubrieating oil or the like to the pump at a constant but adjustable rate at all times and independent of the degree of vacuum developed by the pump; and that it shall be supplied only when the pump is operating and automatically cease to be supplied when the pump stops.

It is the object of the invention to provide a pump lubricating means having the above described desirable mode of operation.

Other objects will be apparent to those skilled in the art to which the invention appertains.

The invention is fully disclosed in the following description taken in connection with the accompanying drawing, in which: r

Fig. 1 is a longitudinal section view of a pump with which the invention may be used, and show,` in-g one embodiment of the invention associated therewith, the parts of the pump beingillustrated somewhat diagrammatically for simplicity:

Fig. 2 is a cross sectional view taken from the plane 2 ofFig. 1, with parts behind the section plane omitted for simplicity, to show more clearly a clamping and adjusting device of Fig. 1;

Fig. 3 is a view similar to a part of Fig. 1 and illustrating a modification of the lubricating means of that figure.

Referring to Fig. 1, the pump shown generally at I has internally thereof a cylindrical chamber 2 against the wall of which eccentrically supported pump vanes 3-3 engage in a well known manner as they are rotatably driven by a shaft 4. The pump has an outer wall 5. Partitions 6 and 1 provide a vacuum chamber 8 with which communicates an intake passage 9 into which a conduit may be screwed; and the construction provides'also an output or pressure chamber I0 into which a conduit may be screwed at II.

Whatever may be the uses of the pump, it is contemplated that during its operation vacuum will be developed in the chamber 8 and that this vacuum will be of different degrees at different times.

A recess I2 is provided at one point of the cylinder Wall 2.V A tube I3 extends into a bore I4 in the cylinder wall and communicatesy with the recess.` The tube has an enlarged head I5 threaded into the outer wall 5 of the pump housing, and the tube I3 has perforations I6 in its wall surrounded by a screen or like filter I'I.

A pipe elbow I8 is threaded into the head I5. A plug I9 is screwed at one of its ends into the open end of the elbow I8 at 20, and at the other end projects into the tube I3. This plug has a bore 2| opening into the elbow I8 and at the opposite end is closed except for a small hole 22, which as an illustrative case, may be the size of a No. 50 drill.

An elbow 23 is threaded into the outer end of the elbow I8. Into the outer end of the elbow 23 isthreaded a tubular shank 24 of an oil'pot 25, or chamber, the shank preferably extending approximately horizontally.

The pot or chamber 25 has an upwardly ex-v tending neck -26. A tubular clamp 2l,- slotted at one side as at 28, is clamped around the neck 26 byr a screw 29 and two ears 30 on the clamp, see also Fig. 2. A reservoir carrier is provided comprisin-g ahead 3I resting upon the clamp 2l', and a tubular internally threaded flange 32 extending upwardly from the head, and an open tube 33 extending downwardly from the head andthrough theneck 26and in tothe pot 25.*; An oil supply reservoir 34 in the form of an inverted cup-,g and preferably being ofglasls to render it transparent so that the' supply of oill therein may be inspected, is threaded at its lower f end into the flange 32'and sealed on'the head 3| at its downwardly open end by a gasket 35.y The f lower end of the tube 33 is preferably out off at an angle as shown. f f f With the arrangement thus far described, oil in the reservoir 34 will flow into the pot 25, shank y24and elbow 23 and air'will take its place in the reservoir until the oil rises tor the level lof the lower open end of the tube 33 as shown; and. f as oil is drawn out of the ypot during operation to be described, oil is rsupplied to it rfrom the reservoir 34, and the level of the oil is thus continuously maintained constant in a well known manner; and the height of the levelA maybe adjusted by adjustably raising or lowering the lower 21, by which it is supported.y .f f f The elbow I8 has a large hole 36, for example 1A inch in diameter, in its rear wall.

1 end yof the tube 33 byraisingior lowering the clamp At `31 isy an elongated piecefofl oilt absorbingl 'f porous material; and because of the practicability, convenience, and cheapness thereof, I prefer to use for this purposea length of ordinary tobacco pipe cleaner,l which as is well .known com prises' a rcentral wire'core surrounded by a mass of fibrous absorbent material. rWhilel other mate-y f rial may beA used for this purpose,l pipe cleaner .material is preferred, butfor. convenience of description will hereinafter be referred to yas porous material.

Theporous materia1'31 extends from the bore into the pot 25.

- The apparatusis preferably assembled in the f following manner. One lend of the porous material 31 is inserted yinto the bore 2l of the plug yI9. The reservoir shank 24 and the.' two elbows I8 and 23 are all three screwed together, The free end of the porous material 31 is then inserted into the small end of the elbow I8 and fed therethrough, and the plug I9 is then screwed into the elbow I8. The elbow I8 is then screwed into the tube head I5.

In operation, the lower end portion of the porous material 31 always lies in, or below the level of, the oil in the shank 24 and therefore absorbs oil. By capillary action the oil rises in and along the porous material up into the elbow I8.

When the pump is working, vacuum is created within the chamber 8 and within the tube I3, and air flows in at the elbow opening 36 and flows over the oil-wet porous material 31 and into and through the bore 2l of the plug I9, through the small hole 22 in the plug, and into thetube I3, and thence to the pump chamber 2.

The bore 2I in the plug and the outside diameter of the porous material 31 are proportioned so that the presence of the porous material in the bore does not prevent the flow of air or air and oil through the plug. This flow of air as described. picks up oil from the oil-wet porous material 31 and carries it through the tube I3 to the pump.

The hole 36 in the elbow I8 is so much larger than the hole 22 in the plug I9, that no appreciable vacuum develops in the elbow I8 regardless of how high a vacuum may be developed by the pump. One result of this is that there is a flow of air through the elbow I8 and over the oil-wet porous material 31 in it, substantially at atmospheric pressure; and consequently the level oi the oil in the shank 24 and pot 25 is not affeoted or changedfby the developed vacuum, but

remains constant at all degrees of vacuum.

The length of that portion of the porous material 31 above they oil level, is therefore constant, because the oil level is constant; and the force of capillarity being a constant,l oil creeps up along that partfof the porous material 31 in the elbows 23 and I8 at a constant rate.

The now of air through the elbowy la and through the small hole 22 in the plug, even at low vacuum, would obviouslyfbe abley to carry oil over into the pump at a high rate if therel were a sutciently ample oilsupply, in the line of air flow, butfitcannot carry it over at a ratey greater than that at which the porous material supplies it, which isat a constant rate, hence at low, high, and intermediate vacuum the rate o oil supplied to the pump is constant. f

rAlsofasr willi nowber apparent, the rate of oil l f supplied to the pump can be adjustablyy changed when desired by adjustably changing the oil level as' described.'r Ify thel oil level is raised, the oil travelingiup the porous material 31 into the elbow f f i8 has a shorter distance to travel 'by capillarity,

and hence :covers this distance in a shorter time and therefore supplies oil at a higher rate. f f The lubricating apparatus f thereforer supplies' f lubricant tothe pump at a rate which is adjusta-A ble, but, when adjusted,tis independent of the cle-l f i i gree of lvacuum in thepump. f l f When the pump stops working, the vacuum actuating the,lubricatordisappearsz; andthe poe: i rous material remains oil-wet; but no oil is car-r f rled therefrom into the pump because the flow of air over it ceases. AMeans to cut off the oil supply; 1

when the pump stops and to turn it on again when f f the pump is to be operated is therefore unnecessary. f

In Fig. 3 .is which'the above described lubricating principles may be embodied and which form may in some cases be preferred.

In this figure, some of the parts of Fig. 1 are reproduced. A fragmgent of the pump of Fig. 1 is shown,as well as the tube I3 having the head I5 described for Fig. 1. A nipple 38 is provided, threaded at its opposite ends and having intermediately thereof a wrench receiving head 39 for turning it. One end of the nipple is closed as at 40 except for a small hole 4I which as in the form of Fig. 1 may be of a size corresponding to a No. 50 drill, and this closed end is screwed into the head I5 at 43. 'I'he other end of the nipple 38 is screwed as at 4`4 into a housing 45 and communicates interiorly therewith.

The housing 45 is generally in the form of `an elbow and its outer or lower end portion 46 is internally threaded as at 41 to receive an exteriorly threaded oil reservoir 48 of glass or other transparent material sealed to the housing by a gasket 49.

Within the elbow housing 45 and carried thereby is the followlng structure. A tube 50, which may be of copper or other metal, and generally vertically disposed, extends through a bore 5I in the wall of the housing 45 and is open to the atmosphere at its upper end as at 52 and is soldered or otherwise secured to and sealed to the housing by solder or the like at 53.

The tube 50 extends downwardly through and below the lower end of the housing 45 whereby its lower end will be disposed in, and near to the bottom of, the reservoir 48 in its mounted position, and therefore immersed in the supply of oil 54 containedin the reservoir. At its lower illustrated another rstructure inz end, the tube 50 extends horizontally as at 55 and joins a riser tube 58, the riser tube at its lower end being closed except for a small drilled opening 51. y

The riser tube 58 extends upwardly and out of the oil 54 and at its upper end, as at 58, is bent inwardly and over the side wall 59 of a metal cup indicated generally at 50.

The cup 80 is upwardly open and the aforesaid tube 58 extends through the cup bottom through a suitable perforation therein, and the juncture is preferably sealed, for example, by solder 8|.

The cup bottom is provided with a downward extending tubular portion 62 closed at its lower end.

A length of pipe cleaner porous material v153', as identified and described in connectionwith Fig. 1, has one end thereof projecting into the cup bottom extension 82 to support and position it, and above the cup 80 it extends upwardly through the elbow housing 45 and its other end lies in the interior of the nipple 38.

The operation of this form of the lubricator is as follows. When vacuum is produced by the pump in the chamber 8 and tube I3, atmospheric air flows into the pipe 50 at its open end 52, through this pipe and upwardly through the riser tube 56 and out at its discharge end 58 into the interior of the housing 45, whence it flows through the nipple 38 and through the small hole 4l into the tube I3 and into the pump.

The internal size of the pipes 50, 55, and 5S through which the air iiows may be so large compared with the size of the little hole 4I in the nipple 38 that development of vacuum in the housing 45 may be completely prevented by the ow of air thereinto through said pipes. The interior of the housing 45 may thereby be maintained at all times substantially at atmospheric pressure, whether the pump-developed vacuum is high or low or intermediate. But in this form of the invention it is not essential to have atmospheric pressure in the housing 45 because the change of pressure cannot change the oil level in the cup 80; so that the relative sizes of the pipes and the hole 4I is not critical; and the device will operate satisfactorily if the pipes are large enough to supply a sufficient ilow of air to effect lubrication as described. For a hole 4| of the size of a No. 50 drill, pipes 13e inch to Tie inch internal diameter will sufdce.

In the drawing the oil 54 is shown as filling the lower part of the pipe line, 5117-55-56, this being the normal or idle condition, and the air owing as described, displaces the oil, causing it to ow out of the pipe 56 at the orifice 58 and into the cup 60.

As the flow of air upwardly through the riser tube 56 continues, it draws oil into it through the I orifice 51 and continuously discharges it together with the air at the discharge outlet 58 into the cup 60 and lls the cup and maintains it full of oil, the excess overflowing from the cup back into the reservoir 54. By this means, a level of oil in the cup 60 is maintained at a constant distance below the nipple 38.

The porous material 63 picks up oil from the cup 60 by capillarity and it rises up and along the material in the housing 45.

The flow of air through the housing 45 and through the nipple 38 ilows over the oil-wet porous material 63 and picks up oil therefrom and carries it on through the small hole 4l into kthe tube i3 and into the pump.

The distance which the oil must creep up along the pipe cleaner material 63 is at all times constant and does not vary with withdrawal of oil 54 from the reservoir 48, because this distance is determined by the level of the oil in the cup 60 which is at all times constant.

In this form, as in the form of Fig. l, the rate of oil feed to the pump is constant being determined by the vertical distance over which oil travels by capillarity in the porous material 63.

While thetwo forms of the invention (Fig. 1 and Fig. 3) differ in appearance, they have featuresvin common, respectively. They each have a rellable oil reservoir 34 and 48; and a receptacle 24 and 60 in which oil is maintained at a constant lower supply level; a porous capillary element 3l and 83 contacting the oil at said level and raising oil by capillarity to a higher level. Each form has a walled enclosure which contains the oil and keeps it from spilling out due to any cause and from becoming contaminated by foreign matter. Each form has a substantially unrestricted atmospheric-air-inlet 36 and 52 to the enclosure, and an air flow restriction 22 and 4l between the enclosure and the vacuum pump chamber; and the upper-level portion of the porous capillary element is disposed so that air owing from the enclosure to the vacuum chamber ows over it.

The restrictions 22 and 4| are small enough not to interfere with the development of the maximum desired useful vacuum in the pump; but at the same time allow air to flow over the upper portion cf the oil-wet porous capillary element, even at low vacuum, at a rate great enough to carry away the oil from it as fast as it raises the oil by its capillarity. Hence in both forms for a given oil supply level and a given length of capillary element above the oil supply level, the rate at which oil is supplied to the pump is constant at all degrees of vacuum. In both forms, the feed of oil to the pump stops when the pump stops working and ceases to develop vacuum.

My invention is not limited to the exact details of construction shown and described but comprehendsv all changes and modifications that come within the scope of the appended claims.

I claim:

1. A lubricator for an air pump having a vacuum chamber, comprising: an oil-containing walled enclosure; means to maintain oil in the enclosure at a constant predetermined level; a

capillary element having a lower portion contacting the oil. and an upper portion to which it raises oil by capillarity to a level above the predetermined level; an air ow conduit communication between the interior of the enclosure and the pump vacuum chamber; an air ilow restriction in said conduit communication; a substantially unrestricted atmospheric air inlet to the enclosure interior; whereby vacuum developed-in the pump vacuum chamber causes air to enter the enclosure at the air inlet and ilow out of the enclosure to the chamber through the restriction; and the said upper portion of the capillary ele,- ment being disposed in the line of air flow between the enclosure interior and the restriction.

2. A lubricator for a pump having a vacuum chamber, comprising: a walled enclosure; a capillary element in the enclosure disposed to have an upper and a lower portion; means to maintain a supply of oil in the enclosure and on the lower portion of the capillary element, at a preselected constant elevation thereon; the capillary element adapted to raise oil from the lower to the upper portion by capillarity; conduit means providing an air flow passageway directly from ambient atmospheric air to the vacuum chamber and through which vacuum in the vacuum chamber causes air to flow; and the upper portion of the capillary element being disposed in the line of the air flow.

3. A lubricator for a, pump having a vacuum chamber, comprising: a walled passageway communicating at on end with the vacuum chamber; a walled enclosure communicating with the other end of the passageway; a substantially unrestricted' air owinlet to the enclosure; an air ow restriction in the passageway; the enclosure comprising an oil receptacle; an oil reservoir above the receptacle; means comprising a gravity supply tube communicating with the receptacle and reservoir, and maintaining a constant oil level air flow inlet.

CARL iF. DUERR, JR.

REFERENCES CITED The' following references are of record in the le of this patent:

UNITED STATES PA'I'ENTS Number Name Date 1,684,395 Hapgood Sept. 18, 1928 2,018,341 Badger Oct. 22, 1935 2,272,926 Squiller Feb. 10, 1942 

